Gerald Mosse has been called up to take the plum ride on Aidan O'Brien's St Leger winner Leading Light in Sunday's Prix de l'Arc de Triomphe at Longchamp.

With the Ballydoyle supremo's son Joseph – in the saddle when winning the Classic at Doncaster and the Queen's Vase at Royal Ascot – unable to get down to 8st 11lb, the allocated weight for three-year-olds in the race, Mosse's services have been snapped up.

O'Brien will also run the Epsom Derby winner Ruler Of The World, which will maintain his partnership with Ryan Moore, but both Camelot and Kingsbarns have been taken out of the race.

O'Brien, who saddled Dylan Thomas to win France's most prestigious race in 2007, reports both in great form ahead of their trip to Paris.

"Ruler Of The World ran really well in his Arc trial in France on his last run," he said. "We have been very happy with him since, he goes there in good form and we hope he runs well. Leading Light has not done a lot since the Leger. We are happy with what he has done."

Now considered a veteran at 46, Mosse won the 1990 Arc on Saumarez and has claimed plenty of the biggest races in the world, including the Melbourne Cup and several of Hong Kong's major prizes.

Leading Light was supplemented yesterday morning by his Coolmore owners, along with Criquette Head-Maarek's Treve and Meandre, at a cost of €100,000 each.

"I'm extremely happy to have got the ride," said Mosse.

"I put my services forward for the ride some time ago when I learned that my intended mount, Chicquita, was to be sold by her owner and would not be running. They rang me back and obviously I'm very grateful. I have ridden for Mr O'Brien before but not in the Arc.

"I would not have a worry about the ground if it turned soft. Today the ground was just on the soft side of good but we are expecting rain tonight.

"The horse looks extremely strong and solid and that is just what you need to win an Arc. I've won the race before and it would be good to put my name back up there among the winners again.

"He gets a three-kilo (8lb) allowance as a three-year-old which is very helpful and I'm very happy to be riding him."

The Fugue has been left in by John Gosden and not declared for the Prix de l'Opera leaving a field of 19 with the final chance to withdraw this morning, when the all-important draw will take place.

The impressive Irish Champion Stakes winner has been cut to 16/1 from 20s by Coral.